Roadway shoulder rumble strips apparatus

ABSTRACT

Rumble strips slow down the speed of tires that are crossing the rumble strips that the vehicle tends to turn its direction toward the shoulder. Also, a component of the reaction force from the rumble strips pushes the vehicle further away from its normal path. These two effects cause potential danger to the driver. The current invention shows a rumble strips apparatus that are capable of providing a guiding force to guide the vehicle back to its normal path and in the mean time, providing vibration as conventional rumble strips do.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] (Not Applicable)

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] (Not Applicable)

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTINGCOMPACT DISK APPENDIX

[0003] (Not Applicable)

BACKGROUND OF THE INVENTION

[0004] Rumble strips usually refer to a series of spaced, generallyparallel grooves, depressions, or ribs in the surface of a roadwayshoulder. Rumble strips can be created by cutting, grinding, orimpressing the surface of the roadway in a pattern designed to alert thedriver of a vehicle to a potential danger or change in conditions ahead.As used herein, the term roadway refers to the hard surface of a road orhighway (including an interstate highway) that is intended for vehiculartraffic. The term roadway shoulder refers to the edges of a roadway.

[0005] The use of rumble strips on the surface of the roadway shoulderis well known. As a vehicle's tires travel across the rumble strips onthe surface of a roadway shoulder, a significant vibration is createdwhich may be both felt and heard by the driver. However, rumble stripsslow down the speed of tires that are crossing the rumble strips due tothe resistance between the tires and the rough surface of the rumblestrips. On the other hand, the speed of tires on the other side of thevehicle is not reduced. Therefore, under these unequal speeds, thevehicle tends to turn its direction toward the shoulder. Besides, a partof the reaction force from the rumble strips pushes the vehicle furtheraway from its normal path. These two effects cause potential danger tothe driver.

[0006]FIG. 1 shows a conventional rumble strips arrangement. In FIG. 1,the traffic in the rightmost (outer) travel lane 1 and the leftmost(inner) travel lane 2 are all moving in the same travel direction 4,which is toward the upper side of the paper. The rightmost travel lane 1and the leftmost travel lane 2 are separated by a lane line 3. On theright of the rightmost travel lane 1 is a right edge line 12. On theright of the right edge line 12 is a right shoulder 13. In the rightshoulder 13, there lies a plurality of rumble strips 14 which aresubstantial perpendicular to the right edge line 12. Similarly, on theleft of the leftmost travel lane 2 is a left edge line 22. On the leftof the left edge line 22 is a left shoulder 23. In the left shoulder 23,there lies a plurality of rumble strips 24 which are substantialperpendicularly to the left edge line 22.

[0007] The problems of the conventional rumble strips as shown in FIG. 1can be illustrated in FIG. 2 and FIG. 3. In FIG. 2, a vehicle istraveling through the rightmost travel lane 1 in the direction of traveldirection 4. When the vehicle is driving off road in a first position15, shown in dotted line, where the vehicle is crossing the right edgeline 12 and its right front wheel hit on the surface of the rumblestrips 14, the vehicle is now in its first direction 17. Since the roughsurface of the rumble strips 14 provide much more resistance than theregular road surface of the rightmost travel lane 1 does, the right sideof the vehicle tends to slow down while the left side of the vehiclekeep on its regular speed. These different speeds of the movement ondifferent sides of the same vehicle cause the vehicle to turn toward theright shoulder 13. There is yet another problem. The rough surface ofthe rumble strips 14 provides a reaction force 170 back to the vehicle.The reaction force 170 has a direction perpendicular to the rumblestrips 14. The reaction force 170 can be decomposed into a firstcomponent 170 x and a second component 170 y. Where the second component170 y has a direction opposite to the first direction 17 and therefore,it cancels out some force from the vehicle and reduce the speed on theright front wheel. On the other hand, the first component 170 x is aforce that has a direction to the right and is parallel to the rumblestrips 14. The force of the first component 170 x, therefore, pushes thevehicle further away from its normal travel direction 4. The vehicle isnow in a second position 16 and a second direction 18 which is furtheraway from its normal travel direction 4. Now both the right front wheeland the right rear wheel hit on the rumble strips 14. Rumble strips 14provide even more resistance back to the right side of the vehicle thatreduces more speed on the right side of the vehicle. The reactions force180 provided by the rumble strips 14 have a first component 180 x and asecond component 180 y. Where the second component 180 y has a directionopposite to the second direction 18 and therefore, it cancels out someforce from the vehicle and reduce the speed on the right wheels. On theother hand, the first component 180 x has a direction to the right andis a force that is parallel to the rumble strips 14. Since the firstcomponent 180 x is larger than the first component 170 x due to a largerangle between the vehicle's direction and the perpendicular line of therumble strips. The force of the first component 180 x pushes the vehicleeven further away from its normal travel direction 4. Before the drivertake control of the wheel and turn it back to its normal path, thevehicle is driving toward a direction further away from its normaltravel direction 4. We discovered that this change of direction is theside effect of the conventional rumble strips 14.

[0008] The side effects of the conventional rumble strips happens on therightmost travel lane 1 also happens on the leftmost travel lane 2 onlythat it mirrors the corresponding parts. A reader should be able tounderstand the details shown in FIG. 3 by understanding the detailsdescribed in the previous paragraph.

BRIEF SUMMARY OF THE INVENTION

[0009] It is an object of the present invention to provide a roadwayshoulder rumble strips which is capable of providing a guiding force toguide the vehicle back to its normal path and in the mean time,providing vibration as conventional rumble strips do.

[0010] A rumble strips apparatus in the surface of a roadway shoulder isprovided. Each of the rumble strip and the right edge line forms anangle of between 0 degree and 60 degrees. The reaction force from therumble strips back to the vehicle can be decomposed into two components.Although one of the components is against the direction of the vehicle,the other component is a net force that pushes the vehicle back to itsnormal path.

[0011] In order to facilitate an understanding of the invention, thepreferred embodiments of the invention are illustrated in the drawings,and a detailed description thereof follows. It is not intended, however,that the invention be limited to the particular embodiments described orto use in connection with the apparatus illustrated herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a conventional rumble strips.

[0013]FIG. 2 shows the direction change on the rightmost lane onconventional rumble strips.

[0014]FIG. 3 shows the direction change on the leftmost lane onconventional rumble strips.

[0015]FIG. 4 is the rumble strips of the current invention.

[0016]FIG. 5 illustrates the reaction force of the current invention.

[0017]FIG. 6 is another example of the current invention.

DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention provides a modified rumble strips apparatusthat is illustrated in FIG. 4 and FIG. 5. In FIG. 4, the traffic in therightmost (outer) travel lane 1 and the leftmost (inner) travel lane 2are all moving in the same travel direction 4, which is toward the upperside of the paper. The rightmost travel lane 1 and the leftmost travellane 2 are separated by a lane line 3. On the right of the rightmosttravel lane 1 is a right edge line 12. On the right of the right edgeline 12 is a right shoulder 13. In the right shoulder 13, there lies aplurality of rumble strips 34. A plurality of rumble strips 34 and theright edge line 12 forms an angle of about 45 degrees. Similarly, on theleft of the leftmost travel lane 2 is a left edge line 22. On the leftof the left edge line 22 is a left shoulder 23. In the left shoulder 23,there lies a plurality of rumble strips 44. A plurality of rumble strips44 and right edge line 22 forms an angle of about 45 degrees.

[0019] Now let's investigate what happen when the vehicle is driving offroad as shown in FIG. 5. In FIG. 5, a vehicle is in a first position 35,shown in dotted line, where the vehicle has across the right edge line12 and its right front wheel hit on the surface of rumble strips 34.Since the rumble strips 34 provide much more resistance than regularroad surface of the rightmost travel lane 1 provides, the right side ofthe vehicle tends to slow down while the left side of the vehicle keepon the regular speed as the conventional rumble strips do. However,since the rumble strips 34 and the right edge line 12 forms an angle ofabout 45 degrees. The reaction force 370 is in a direction perpendicularto the rumble strips 34. The reaction force 370 can be decomposed into afirst component 370 x and a second component 370 y. Where the secondcomponent 370 y has a direction opposite to the first direction 37 andtherefore, it cancels out some force from the vehicle and reduce thespeed on the right front wheel. However, the first component 370 x is aforce that is direct to the left and therefore, pushes the vehicle backto its normal travel direction 4.

[0020] Again, a reader should be able to understand the details on theleftmost travel lane 2 by understanding the details described in theprevious paragraph.

[0021] There are other species of this invention. FIG. 6 shows anexample of other embodiments. In FIG. 6, the rumble strips 54 a, 54 b,64 a, and 64 b are all curve lines. However, for each of the rumblestrips, the two ends of a rumble strip form a virtual line. This virtualline and the edge line 12 (22 for 64 a and 64 b) still form an angle ofabout 45 degrees. Therefore, for each rumble strip, some segmentsprovide a larger reaction force component than other segments in thesame rumble strip. However, when a vehicle hits on the rumble strips 54a, 54 b, 64 a, or 64 b, the vehicle still get a reaction force componentthat pushes the vehicle back to its normal travel direction.

[0022] Although the description above shows that the rumble strips andthe edge line form an angle of about 45 degrees, the angle can be of anyvalue between 0 degree and 60 degrees. Usually, when a vehicle isdriving off road, the vehicle's longitudinal axis and the edge line forman angle of at most 30 degrees. Therefore, as long as the angle formedby the rumble strips and the edge line is less than 60 degrees, one ofthe reaction force components will direct the vehicle back to its normaldirection.

[0023] Various modifications and alternative embodiments such as wouldordinarily occur to one skilled in the art to which the inventionrelates are also contemplated and included within the scope of theinvention described and claimed herein.

We claim:
 1. (cancelled)
 2. (cancelled)
 3. (cancelled)
 4. (cancelled) 5.A roadway shoulder rumble strips comprising: a rightmost travel lane; aright edge line lies on the right of said rightmost travel lane; a rightshoulder located on the right of said right edge line; and a pluralityof curved rumble strips lies in the said right shoulder where the twoends of each of said plurality of curved rumble strips form a virtualline and the said virtual line and said right edge line form an angle ofapproximately 5-15°.
 6. An apparatus as in claim 5, where the most partof each of the said curved rumble strips are on the left side of each ofthe said virtual line.
 7. An apparatus as in claim 5, where the mostpart of each of the said curved rumble strips are on the right side ofeach of the said virtual line.
 8. A roadway shoulder rumble stripscomprising: a leftmost travel lane; a left edge line lies on the left ofsaid leftmost travel lane; a left shoulder located on the left of saidleft edge line; and a plurality of curved rumble strips lies in the saidleft shoulder where the two ends of each of said plurality of curvedrumble strips form a virtual line and the said virtual line and saidleft edge line form an angle of approximately 5-15°.
 9. An apparatus asin claim 8, where the most part of each of the said curved rumble stripsare on the right side of each of the said virtual line.
 10. An apparatusas in claim 8, where the most part of each of the said curved rumblestrips are on the left side of each of the said virtual line.